Recently, a high quality image signal processing apparatus such as a digital television (TV) not only provides a TV broadcasting function, but also provides a function of allowing data stored in a universal serial bus (USB) memory to be viewed through a high quality TV by connecting the USB memory to the high quality image signal processing apparatus, provides a digital video recorder function of recording TV broadcasting, and provides a digital versatile disc (DVD) player function, and a Divx player function.
Though a digital TV having a variety of built-in additional functions therein is brought to the market, necessary additional functions are different depending on a user's taste. Therefore, a digital TV or a high quality image signal processing apparatus having built-in additional functions therein is not sufficient to meet the tastes of various users.
Therefore, it is required to provide an image signal processing apparatus that can selectively mount a module having an additional function and provide wide compatibility between modules having additional functions, respectively.